Acids

Acids have an excess on H+ ions, the more H+ ions the
more acidic the solution.

Acids turn universal indicator yellow, orange or red

Acids turn blue litmus paper red

Acids turn phenolphthalein solution clear

Acids have a pH numbers less than 7

All acids are solutions of pure compounds in water.Solutions of non-metal oxides are acidic

SO2 sulphur dioxide

CO2 carbon dioxide

P2O5 phosphorus (V) oxide

Some common acids

Mineral Acids

Hydrochloric Acid HCl strong acid

Sulphuric Acid H2SO4 strong acid

Nitric Acid HNO3 strong acid

Phosphoric Acid H3PO4 strong acid

Carbonic Acid H2CO3 weak acid

Organic Acids

Citric Acid C6H8O7 weak
acid

Ethanoic Acid CH3COOH weak acid

Methanoic Acid HCOOH weak acid

Lactic Acid CH3CH(OH) weak acid

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COOH

Acids react with metals to form salts

A salt is a compound made from acid when a metal takes the place of the hydrogen in the acid.

Acid + metal à Salt + Hydrogen

2HCl(aq) + Zn(s) à ZnCl2(aq) + H2(g)

H2SO4(aq) + Mg(s) à MgSO4(aq) + H2(g)

2HNO3(aq) + 2Na(s) à 2NaNO3(aq) + H2(g)

2H3PO4(aq) + 3Ca(s) à Ca3(PO4)2(aq) + 3H2(g)

3H2CO3(aq) + 2Al(s) à Al2(CO3)3(aq) + 3H2(g)

The salt made depends on the acid

HCl à chlorides

H2SO4 à sulphates

HNO3 à nitrates

H3PO4 à phosphates

H2CO3à carbonates

Bases/Alkalis

Alkaline solutions have an excess of OH- ions.The more OH- ions the more alkaline the solution.

Alkaline solutions turn universal indicator blue,
purple and violet

Alkaline solutions turn red litmus paper blue

Alkaline solutions turn phenolphthalein pink

Alkaline solutions turn methyl orange yellow

Alkaline solutions have a pH greater than 7

Metal oxides dissolve in water to form alkaline
solutions

Na2O Sodium oxide

MgO Magnesium oxide

CaO Calcium oxide

So what is the difference between
alkalis and bases?

Alkalis are substances that dissolve in water to give a pH greater than 7

Alkalis turn red litmus paper blue

Alkalis neutralize acids to form a solution with a pH 7.

Bases are metal oxides and metal hydroxides which are insoluble in water.

Bases neutralize acids to form a solution with a pH 7.

Therefore Alkalis are a subset of a group of chemicals that can neutralize acids.

Alkalis are soluble bases.

All alkalis are bases, but not all bases are alkalis.

Common Alkalis

NaOH sodium hydroxide strong alkali

KOH potassium hydroxide strong alkali

Ca(OH)2 calcium hydroxide (limewater) strong alkali

NH3(aq) or NH3OH ammonia solution or ammonium hydroxide weak alkali

Common Bases

CaO calcium oxide strong base

MgO magnesium oxide strong base

Acids react with bases to form salts + water

This is a neutralization reaction.

acid + base à salt + water

HCl(aq) + NaOH(aq) à NaCl(aq) + H2O(l)

HCl(aq) + KOH(aq) à KCl(aq) + H2O(l)

2HCl(aq) + MgO(aq) à MgCl2(aq) + H2O(l)

2HCl(aq) + CuO(aq) à CuCl2(aq) + H2O(l)

HNO3(aq) + NaOH(aq) à NaNO3(aq) + H2O(l)

HNO3(aq) + KOH(aq) à KNO3(aq) + H2O(l)

2HNO3(aq) + MgO(aq) à Mg(NO3)2(aq) + H2O(l)

2HNO3(aq) + CuO(aq) à Cu(NO3)2(aq) + H2O(l)

H2SO4(aq) + 2NaOH(aq) à Na2SO4(aq) + 2H2O(l)

H2SO4(aq) + 2KOH(aq) à K2SO4(aq) + 2H2O(l)

H2SO4(aq) + MgO(aq) à MgSO4(aq) + H2O(l)

H2SO4(aq) + CuO(aq) à CuSO4(aq) + H2O(l)

H3PO4(aq) + 3NaOH(aq) à Na3PO4(aq)
+ 3H2O(l)

H3PO4(aq) + 3KOH(aq) à K3PO4(aq) + 3H2O(l)

2H3PO4(aq) + 3MgO(aq) à Mg3(PO4)2(aq) + 3H2O(l)

2H3PO4(aq) + 3CuO(aq) à Cu3(PO4)2(aq) + 3H2O(l)

Acids react with carbonates to give salt, water
and carbon dioxide

Acid + metal carbonate à salt + water + carbon dioxide

2HCl(aq) + CaCO3(s) à CaCl2(aq) + H2O(l) + CO2(g)

H2SO4(aq) + Na2CO3(s) à Na2SO4(aq) + H2O(l)
+ CO2(g)

General Study Tips

How to outline a chapter/section.

1) Read the chapter/section carefully. If you don't understand a section or concept write down a question to ask
in class the next day.

2) Read the chapter/section objectives at the beginning of the chapter.

3) Write down one objective at the top of a blank piece of paper.

4) Re-read the chapter/section, keeping in mind the objective that you have written. Any information that pertains
to that objective write down underneath your objective. When you are sure that you have written down all the information
on that objective, write down the second objective on a new piece of paper and start the process again.

Tip- write only one objective per piece of paper--save room for class notes and class problems.